Shock absorber for automobiles



June 23, 1925. 1,543,098

N. CARTER ET AL SHOCKABSORBER FOR AUTOMOBILES Filed July 16, '1924Patented `lune 23, 1925.

UNITED STATES vPATENT oFFicE.

SHOCK BSCH-BER FOB y AUTOMOBILE.

Application led July 16, 1924. Serial No. 726,258.

To all fwlwm 'it may concern.'

Be it known that we, NICHOLAs CARTER, a citizen of Austria, and MILANKRIvoxUCHA, a citizen of the United States, both residing at Chicago, inthe county of Cook and State of Illinois, have invented Certain new anduseful Improvements in a Shock Absorber for Automobiles; and we dohereby declare the. following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit ap ertains to make and use the same.

ur invention relates to shock absorbers and particularly to the class ofshock absorbers employed on automobiles for checking the 'rebound afterthe wheels oilv a vehicle have passed over any s udden Airregularity vinthe street or road over whichp'the automobile is traveling..

For this purpose, our invention aims to provide a shock absorber whichwill yieldingly resist the downward movement of the body of theautomobile and which will instantly and more strongly resist thesubsequent upward rebound of the vehicle body. It also aims to provide ashock 'absorber for this purpose which will be exceedingly sim le andstrong in construction, and which willbe self-lubricating as to itsoperating portions. Furthermore, our invention aims to Vprovide a shockabsorber which. can readily be attached'even by inexperienced persons tostandard types of automobiles, and aims to provide it with attachingmeans aiording a free suspension of the shock absorber propenso as toallow f0r,the normal shifting of the relative positions of the vehicleparts between which the shock absorber is interposed. f

Still further and also more detailed objects will appear from thefollowing specification and from the accompanying drawin in which A p1g. 1 is a erspective view of a' shock absorber emb ying our invention,includlng dotted lines showing portions of a vehicle between which thisshock absorber is 'interposed.

Fig. 2 is an enlarged central and vertical section through the mainportion of the shockabsorber of Fig. 1, with portions of the pistonhead-broken away to show the ports in this head and the port-closingiiap as the latter appears when the piston is moving downwardly withrespect to the cylinder.

`12 of a piston by means of a bushing Fig. 3 is an enlarged central andvertical section through the head end of the iston showing the positionof the port-c osing flap when the piston is moving upwardly with respectto the cylinder and showing the method of assembling the piston head andthe adjacent parts.

Fig. 4 is a horizontal section lookin up- Wards and taken from the line4 4 of 1g. 3.

Fig. 5 is a fragmentary enlarged view of the socketing end of the clampin which the free'end of the piston rod is swiveled.

Fig. 6 is an enlarged section taken through the axis of .the two boltsin the same figure in the plane of the line 6-6 of Fig. 1. y

In the embodiment of the drawings, our shock absorber includes a casinghavin a c lindrical wall 1 and havingl caps 2 an 3 t readed res ectivelyupon its upper and lower'ends. ecured to the upper cap 2 is a supportingshank 4 which carries at its uper end a ball 5'adapted to form part of aall-and-socket connection to a bracket 6. This bracket has two parts 7and 8 each provided with a hole for receivin a bolt," thereby adaptingthis clamp to secured to chassis or vehicle body portions ofvariousshapes.

The cap 3 at the lower end of the cylinder has a tubular extension 9provided with an interior shoulder 10 against which loose packing 11 canbe clamped against the stem 13 threaded into the said tubular extension9, thereby affording an effective stuiiing' box. The piston stem 12 isfastened at its upper end to a piston head which desirably com prises apair of metal disks 14 and 15 Clamping a leather disk 16 between them,this4 leather disk being of a diameter slidabl itting the bore of thecylinder tube 1 while the metal disks 14 and 15 are both sli htlysmaller than this diameter. ixtending vertically through the piston headare a pair of ports 17 and 18, the latwe desirably provide a stitliener20 under the said flap, which stiiiener is desir-ably of metal. Thisstiener terminates radially inward of the piston from the said port 18,so that it limits the fiexing of the i'lap to the portion adjacent tothe port 18 and prevents the flap from iiexing to such an extent that itwould not promptly close the port 18 when the piston moves downward withrespect to the cylinder as hereafter described. To facilitate such anassembly, we desirably reduce the upper end of the piston rod or stem 12soas to aii'ord a stem portion 21 of smaller diameter than the mainportion of this stem. This smaller diametered stem portion 21 extendssuccessively through alined bores in the stiffcner 20, the flexible flap19, the lower metal disk 15, the leather. disk 16 and the upper metaldisk 14. Then we thread the upper end of this piston stem portion 21 toreceive a nut 22 which clamps the said perforated parts against theshoulder at the juncture of the stem portions 12 and 21.

' The 'lower end of the piston stem 12 is vprovided with a ball-shapedenlargement 23 which is socketed in one end of a lower attaching clamp24, this clamp being constructed so that it can readily be attached toanother vehicle portion, as for example by attaching it to a body spring25 by a U-bolt 26 after the manner shown in Fig. 1. To provide theneeded ball and socket connection for this purpose, we desirably providethe said lower attaching clamp with a riser portion 27 having asubstantially hemispherical recess 28 in its outer face, this recessbeing continued to the top of the clamp by a substantiallysemi-cylindrical groove-29 of aY diameter somewhat larger 'than' thestem 12. Then we provide a companion socket piece 30 having a hollowhemispherical portion facing the said hemispherica-l depression 28, thisclamping piece 30 being secured to the riser 27 by bolts 31 as shown inFig. 1. `,The upper attaching clamp has a free end 32 extendingdownwardly and formed similar to the .recessed riser of the lowerattaching clamp but directed downwardly, and this upper clamp alsoincludes a companion socket piece 33 formed similarly to the part 30 andbolted to the part 32 by bolts 34.

When in use, the cylinder of our shock absorber is partly filled with aliquid 35, which desirably is a lubricating oil, and the top of thisliquid terminates at some distance below the lower face of the cap 2 soas to provide an air space 36 above the oil. To allow for this oilfilling, we provide the cap 2 with a threaded opening which is normallyclosed by a plug 37. We also desirably interpose packin disks 38 and 39between the, ends of the cy indrical tube 1 and the two caps 2 and 3',so 7that these will cooperate with the packing 11 in elfectixvelysealing the casin in which the piston head is slidable and t rough thelower end of which casing the piston stem 12 extends.

In Amanufacturing such a shock absorber for anygiven type of vehicle,the lengths of the cylinder tube 1 and the piston stem 12 are soproportioned that the piston head will be near the lower end of thecylinder, a proximate-ly as shown in Fig. 2, when t e vehicle istraveling along a smooth road so that the springs of the vehicle holdthe chassis at a substantially normal height above the running gear.yWhen the wheel adjacent to the shock absorber strikes a bump, thesudden lift-ing .action on this wheel and the corresponding axle willmove the lower attaching clamp and the piston stem upwardly, therebycausing the piston head to slide upwardly in the cylinder. This upwardmovement of the piston head will be resisted by the compressing of theair 36 above the oil and more particularly by the limited size of thevports 17 and 18 through which the oil must flow in passin from abovethe piston head to the space be owe the piston head. During such anupward movementof the piston head (or a corresponding downward movementof the cylinder with respect to the head) the pressure of the oilthrough. the larger port 18 immediatel flexes the flap 19, as to aposition corresponds: ing substantially to that of Fig. 3, so that oilwill pass through this larger port as well as' through the smaller port17. quently, the relative upward movement of the piston with respect tothe cylinder is ymerely slowed downto the rate at which oil can passjointly through both of the ports 17 and 18.

However, when the rebound causes the l the desired difference in thechecking eect of our shock absorber as to both` the initial and therebound movements. During these movements, the upper Aand lowerball-andsocket joints will not remain in the same relative positions,particularly if either the axle or the vehicle body are considerablytilted, but the ball and socket mountings automatically allow for suchchanges with- Consemore severel out cramping or overstraining any of theparts.

By employing a lubricating oil as` the liquld in the cy inder, we alsorovidekor a. suitable lubrication of the plston stem, Y.

thereby insuring a free and easyv movement of the piston in readyresponse to the jolts and the rebounds encountered when the vehicle istraveling even over rough roads.

Additional oil can readily be introduced at any time by merely removingthe plug 37,

but we desirably provide a considerable airv space 36 at all times abovethe oil so as to at the rear of the vehicle, theshocks due to roughroads are greatly reduced. Furthermore, we have found that with ourshock absorbers arranged as described, an increased loading of thevehicle body will assist in checking the rebound. Consequently, ourshock absorbers are equally effective with lightly loaded and wellfilledautomobiles, thus requiring1 no adjustmentaccordin to the-load on t evehicle.

' owever, while we have illustrated and described our invention in ahighly desirable em'bfodiment including certain types of attachingclamps and including an exceedingly simple flexible flapas the checkvalve or closure member for restricting the rate at which liquid canpass the iston head,

and have also mentioned certain materials as desirable for theAcorresponding parts, we do not wish to'be limited toy these or otherdetails of the construction and arrangement thus disclosed. Obviously,these mi ht all be modified in many'ways without departing either fromthe s irit of our invention or from the appende claims.

We claim'as our invention g 1. A shock absorber comprising a cylinderpartly filled with a liquid, a piston having a head slidable in thecylinder and a stem extending slidably through one head of the cylinder,the piston head having a continuouslycpen port extending through it andalso a .relatively larger port extending through it, and a check valvedisposed for opening and closing the said larger port according as thepiston is movin in one direction or the other, the check va ve com- `astifening member engaging a part o prising a flexible flap having oneface adapted to bear against one' ace of the piston head, the flapbeingadapted to be flexed away from the said face by the flow of liquidthrough the said larger port,fai}i1d t e flap to'limit the flexing ofthe flap.

2. A shock absorber comprising a c linder partly filledfwith a liquid, apiston avin a head slidable in the cylinder and a. ste

i extending slidably through one head of the cylinder, the piston headhaving a continuously open port extending through it and also arelatively larger port extending through it, and a check valve disposedfor opening and closing the said larger port according as the piston ismoving in one direction or the other, the check valve comprising aflexible flap havin one face adapted to bear against one ace of thepiston head, the flexed awa from of li uid th a sti ening memberengaging the outer face the said face by the flow 'of the flap' andterminating radially inward of. the piston from the said larger port.

3. A shock absorber comprising a cylinder partly filled with a liquid, apiston having a head slidable inthe cylinder and a stem extendingslidably through one head of the. cylinder, the piston head having acontinuously open port extending through it and also a relatively lar erport extending through it, and a chec valve disposed for opening'an'dclosing the said larger port according as the piston is movin in onedirection or the other, the check va ve comprising a flexible flaphaving one face adapted to bear against one face of the piston head, theflap bein adapted to be flexed awa from the said face by the flow ofliquid t rough the said larger port, the stem having a shoulderformation, and a stiffening member clamped between the flap and the saidshoulder formation and engaging a portion of the flap radially inward ofthe piston from the said larger port.

4. A shock absorber comprising a vertical cylinder having a closed u perend and a bore in its lower end, a lu ricatin li uid partially fillingthe cylinder and a or in an air space between the to of the liqui andthe upper end of the cy inder, a piston rough the said larger port, and

flap being adapted to be y having /its head slidable in the cylinder andnormally within the liquid and having its stem extending slidablythrough the said bore, means respectively connecting the upper end ofthe cylinder and the lower end of the piston stem to superposed art ofthe vlliicle which are relatively vertically mova e, ciated therewithfor permitting the assage of the liquid throug the same, and check meansassociated with the piston head for restricting the said passage-afordinmeans when the piston head moves in one irection with res ect to thecylinder.

ggn at Chicago, Illinois, July 12th, 1

NICHOLAS CARTER. x MILAN miivoKUoHA.

the piston head having means assoy

